Parting blade woes

[HughF]

What does everyone use for parting blades? I have an insert holder/blade (32mm deep I think) in a phase2 style toolpost on my LeBlond 15" and that works really well.

On my VSL, I have a dickson style toolpost and have a direct clamping dickson holder that holds 3/4 deep blades. I have a cheapanese 3/4mm insert holder which after light use has now deformed and doesn't hold the inserts properly. It's making me angry...

I'm thinking of going back to a plain hss blade on the VSL. What are the 3/4x1/8 HSS blades with chipbreaker like? I mostly turn steel and S/S with the odd bit of alu.

 

[RonA]

What does everyone use for parting blades? I have an insert holder/blade (32mm deep I think) in a phase2 style toolpost on my LeBlond 15" and that works really well.

On my VSL, I have a dickson style toolpost and have a direct clamping dickson holder that holds 3/4 deep blades. I have a cheapanese 3/4mm insert holder which after light use has now deformed and doesn't hold the inserts properly. It's making me angry...

I'm thinking of going back to a plain hss blade on the VSL. What are the 3/4x1/8 HSS blades with chipbreaker like? I mostly turn steel and S/S with the odd bit of alu.

I've posed this very same question myself on this very forum. I have a 3/4" HSS parting tool rigidly held in a purpose built holder for use on my Myford ML7 but the results have always been disappointing & on occasion the tool tip goes blue losing its temper despite adequate cooling. I often resort to just cutting the job off oversize with a hacksaw & then truing it to the finished size with a carbide tipped tool.
RonA

 

[DanielW]

If your tool is turning blue(oooer!) then your speed is to high.

HughF,try an carbide/hss with the tip just slightly above center level at a medium speed ie anywhere between 100/150 for carbide tool and lower for hss.

 

[DanielW]

It would be in your best interest to have a read and collect a chart in understanding what material and speeds to use on the lathe and aquire a revolution counter and adhere to the chart for turning or parting off.

You can buy a hand held revolution counter on the bay for silly prices.

 

[DanielW]

http://www.ebay.co.uk/bhp/digital-tachometer

 

[MattH]

I always run fairly fast (against all the advice to the contrary).
I also never part off all the way with carbide tips if the material is solid. I always leave a nub and then either break the part of or hacksaw it off.
I find if carbide is going to break it will right at the end of the cut.

Lately I've gone back to solid HSS blades as I find the cheap insert holders deform when the first tip breaks rendering it useless.

 

[DanielW]

The perfect parting tool is the flat tipped round body type,the round body is more rigid in the tool holder and reduces vibration.

 

[HughF]

I always run fairly fast (against all the advice to the contrary).
I also never part off all the way with carbide tips if the material is solid. I always leave a nub and then either break the part of or hacksaw it off.
I find if carbide is going to break it will right at the end of the cut.

Lately I've gone back to solid HSS blades as I find the cheap insert holders deform when the first tip breaks rendering it useless.

Thanks for the advice Matt, this is the exact problem that has happened with this insert holder... Back to hss I think, at least on the vsl. The deeper insert holder on the leblond has never deformed, but it is about 4mm thick.

 

[Gritineye]

I usually part off using power feed and HSS works fine for me on steel.

Don't have a lot of luck SS which is a bit tricky, so maybe an insert tool would be better for that, I haven't tried one yet.

 

[HughF]

After thinking this through, the insert holder for gtn style inserts will never be very strong at 19mm deep. I will get a deeper one, 26mm probably and modify a spare holder I have to carry the deeper blade on centre. I've got too many gtn inserts to walk away from it as a system.

 

[outofthefire]

What does everyone use

My grinder with a slitting disk I know all the reasons not to, my mate, the real engineer only freaks out more if I leave the key in the chuck